Father has a 01 with the 5.9 diesel. With the new low sulfur fuel should he be adding some lubricant to the fuel? Has cummins recommended this? He says his engine sounds different but has gotten better fuel milage. He has about 80,000 miles on it.

 

Does it NEED more lubricant--no, will it hurt to add lubricant--no. Most people do notice a reduction in noise when using a lubricant additive, so I think it helps. I personally use the Power Service because I think it helps keep the injectors clean and in turn helping the mileage. It also quiets ths rattle down a bit, and I don't see how that could be bad.

 

Run B20 and all of your problems will be solved.

 

i use lucas and like it alot!

 

I'm running 1oz of Walmart 2-stroke oil per gallon of fuel. Quiets it right down and helps to protect / lube that costly VP-44.